1/*
2** I/O Sapic Driver - PCI interrupt line support
3**
4**      (c) Copyright 1999 Grant Grundler
5**      (c) Copyright 1999 Hewlett-Packard Company
6**
7**      This program is free software; you can redistribute it and/or modify
8**      it under the terms of the GNU General Public License as published by
9**      the Free Software Foundation; either version 2 of the License, or
10**      (at your option) any later version.
11**
12** The I/O sapic driver manages the Interrupt Redirection Table which is
13** the control logic to convert PCI line based interrupts into a Message
14** Signaled Interrupt (aka Transaction Based Interrupt, TBI).
15**
16** Acronyms
17** --------
18** HPA  Hard Physical Address (aka MMIO address)
19** IRQ  Interrupt ReQuest. Implies Line based interrupt.
20** IRT	Interrupt Routing Table (provided by PAT firmware)
21** IRdT Interrupt Redirection Table. IRQ line to TXN ADDR/DATA
22**      table which is implemented in I/O SAPIC.
23** ISR  Interrupt Service Routine. aka Interrupt handler.
24** MSI	Message Signaled Interrupt. PCI 2.2 functionality.
25**      aka Transaction Based Interrupt (or TBI).
26** PA   Precision Architecture. HP's RISC architecture.
27** RISC Reduced Instruction Set Computer.
28**
29**
30** What's a Message Signalled Interrupt?
31** -------------------------------------
32** MSI is a write transaction which targets a processor and is similar
33** to a processor write to memory or MMIO. MSIs can be generated by I/O
34** devices as well as processors and require *architecture* to work.
35**
36** PA only supports MSI. So I/O subsystems must either natively generate
37** MSIs (e.g. GSC or HP-PB) or convert line based interrupts into MSIs
38** (e.g. PCI and EISA).  IA64 supports MSIs via a "local SAPIC" which
39** acts on behalf of a processor.
40**
41** MSI allows any I/O device to interrupt any processor. This makes
42** load balancing of the interrupt processing possible on an SMP platform.
43** Interrupts are also ordered WRT to DMA data.  It's possible on I/O
44** coherent systems to completely eliminate PIO reads from the interrupt
45** path. The device and driver must be designed and implemented to
46** guarantee all DMA has been issued (issues about atomicity here)
47** before the MSI is issued. I/O status can then safely be read from
48** DMA'd data by the ISR.
49**
50**
51** PA Firmware
52** -----------
53** PA-RISC platforms have two fundamentally different types of firmware.
54** For PCI devices, "Legacy" PDC initializes the "INTERRUPT_LINE" register
55** and BARs similar to a traditional PC BIOS.
56** The newer "PAT" firmware supports PDC calls which return tables.
57** PAT firmware only initializes the PCI Console and Boot interface.
58** With these tables, the OS can program all other PCI devices.
59**
60** One such PAT PDC call returns the "Interrupt Routing Table" (IRT).
61** The IRT maps each PCI slot's INTA-D "output" line to an I/O SAPIC
62** input line.  If the IRT is not available, this driver assumes
63** INTERRUPT_LINE register has been programmed by firmware. The latter
64** case also means online addition of PCI cards can NOT be supported
65** even if HW support is present.
66**
67** All platforms with PAT firmware to date (Oct 1999) use one Interrupt
68** Routing Table for the entire platform.
69**
70** Where's the iosapic?
71** --------------------
72** I/O sapic is part of the "Core Electronics Complex". And on HP platforms
73** it's integrated as part of the PCI bus adapter, "lba".  So no bus walk
74** will discover I/O Sapic. I/O Sapic driver learns about each device
75** when lba driver advertises the presence of the I/O sapic by calling
76** iosapic_register().
77**
78**
79** IRQ handling notes
80** ------------------
81** The IO-SAPIC can indicate to the CPU which interrupt was asserted.
82** So, unlike the GSC-ASIC and Dino, we allocate one CPU interrupt per
83** IO-SAPIC interrupt and call the device driver's handler directly.
84** The IO-SAPIC driver hijacks the CPU interrupt handler so it can
85** issue the End Of Interrupt command to the IO-SAPIC.
86**
87** Overview of exported iosapic functions
88** --------------------------------------
89** (caveat: code isn't finished yet - this is just the plan)
90**
91** iosapic_init:
92**   o initialize globals (lock, etc)
93**   o try to read IRT. Presence of IRT determines if this is
94**     a PAT platform or not.
95**
96** iosapic_register():
97**   o create iosapic_info instance data structure
98**   o allocate vector_info array for this iosapic
99**   o initialize vector_info - read corresponding IRdT?
100**
101** iosapic_xlate_pin: (only called by fixup_irq for PAT platform)
102**   o intr_pin = read cfg (INTERRUPT_PIN);
103**   o if (device under PCI-PCI bridge)
104**               translate slot/pin
105**
106** iosapic_fixup_irq:
107**   o if PAT platform (IRT present)
108**	   intr_pin = iosapic_xlate_pin(isi,pcidev):
109**         intr_line = find IRT entry(isi, PCI_SLOT(pcidev), intr_pin)
110**         save IRT entry into vector_info later
111**         write cfg INTERRUPT_LINE (with intr_line)?
112**     else
113**         intr_line = pcidev->irq
114**         IRT pointer = NULL
115**     endif
116**   o locate vector_info (needs: isi, intr_line)
117**   o allocate processor "irq" and get txn_addr/data
118**   o request_irq(processor_irq,  iosapic_interrupt, vector_info,...)
119**
120** iosapic_enable_irq:
121**   o clear any pending IRQ on that line
122**   o enable IRdT - call enable_irq(vector[line]->processor_irq)
123**   o write EOI in case line is already asserted.
124**
125** iosapic_disable_irq:
126**   o disable IRdT - call disable_irq(vector[line]->processor_irq)
127*/
128
129
130/* FIXME: determine which include files are really needed */
131#include <linux/types.h>
132#include <linux/kernel.h>
133#include <linux/spinlock.h>
134#include <linux/pci.h>
135#include <linux/init.h>
136#include <linux/slab.h>
137#include <linux/interrupt.h>
138
139#include <asm/byteorder.h>	/* get in-line asm for swab */
140#include <asm/pdc.h>
141#include <asm/pdcpat.h>
142#include <asm/page.h>
143#include <asm/io.h>		/* read/write functions */
144#ifdef CONFIG_SUPERIO
145#include <asm/superio.h>
146#endif
147
148#include <asm/ropes.h>
149#include "iosapic_private.h"
150
151#define MODULE_NAME "iosapic"
152
153/* "local" compile flags */
154#undef PCI_BRIDGE_FUNCS
155#undef DEBUG_IOSAPIC
156#undef DEBUG_IOSAPIC_IRT
157
158
159#ifdef DEBUG_IOSAPIC
160#define DBG(x...) printk(x)
161#else /* DEBUG_IOSAPIC */
162#define DBG(x...)
163#endif /* DEBUG_IOSAPIC */
164
165#ifdef DEBUG_IOSAPIC_IRT
166#define DBG_IRT(x...) printk(x)
167#else
168#define DBG_IRT(x...)
169#endif
170
171#ifdef CONFIG_64BIT
172#define COMPARE_IRTE_ADDR(irte, hpa)	((irte)->dest_iosapic_addr == (hpa))
173#else
174#define COMPARE_IRTE_ADDR(irte, hpa)	\
175		((irte)->dest_iosapic_addr == ((hpa) | 0xffffffff00000000ULL))
176#endif
177
178#define IOSAPIC_REG_SELECT              0x00
179#define IOSAPIC_REG_WINDOW              0x10
180#define IOSAPIC_REG_EOI                 0x40
181
182#define IOSAPIC_REG_VERSION		0x1
183
184#define IOSAPIC_IRDT_ENTRY(idx)		(0x10+(idx)*2)
185#define IOSAPIC_IRDT_ENTRY_HI(idx)	(0x11+(idx)*2)
186
187static inline unsigned int iosapic_read(void __iomem *iosapic, unsigned int reg)
188{
189	writel(reg, iosapic + IOSAPIC_REG_SELECT);
190	return readl(iosapic + IOSAPIC_REG_WINDOW);
191}
192
193static inline void iosapic_write(void __iomem *iosapic, unsigned int reg, u32 val)
194{
195	writel(reg, iosapic + IOSAPIC_REG_SELECT);
196	writel(val, iosapic + IOSAPIC_REG_WINDOW);
197}
198
199#define IOSAPIC_VERSION_MASK	0x000000ff
200#define	IOSAPIC_VERSION(ver)	((int) (ver & IOSAPIC_VERSION_MASK))
201
202#define IOSAPIC_MAX_ENTRY_MASK          0x00ff0000
203#define IOSAPIC_MAX_ENTRY_SHIFT         0x10
204#define	IOSAPIC_IRDT_MAX_ENTRY(ver)	\
205	(int) (((ver) & IOSAPIC_MAX_ENTRY_MASK) >> IOSAPIC_MAX_ENTRY_SHIFT)
206
207/* bits in the "low" I/O Sapic IRdT entry */
208#define IOSAPIC_IRDT_ENABLE       0x10000
209#define IOSAPIC_IRDT_PO_LOW       0x02000
210#define IOSAPIC_IRDT_LEVEL_TRIG   0x08000
211#define IOSAPIC_IRDT_MODE_LPRI    0x00100
212
213/* bits in the "high" I/O Sapic IRdT entry */
214#define IOSAPIC_IRDT_ID_EID_SHIFT              0x10
215
216
217static DEFINE_SPINLOCK(iosapic_lock);
218
219static inline void iosapic_eoi(void __iomem *addr, unsigned int data)
220{
221	__raw_writel(data, addr);
222}
223
224/*
225** REVISIT: future platforms may have more than one IRT.
226** If so, the following three fields form a structure which
227** then be linked into a list. Names are chosen to make searching
228** for them easy - not necessarily accurate (eg "cell").
229**
230** Alternative: iosapic_info could point to the IRT it's in.
231** iosapic_register() could search a list of IRT's.
232*/
233static struct irt_entry *irt_cell;
234static size_t irt_num_entry;
235
236static struct irt_entry *iosapic_alloc_irt(int num_entries)
237{
238	unsigned long a;
239
240	/* The IRT needs to be 8-byte aligned for the PDC call.
241	 * Normally kmalloc would guarantee larger alignment, but
242	 * if CONFIG_DEBUG_SLAB is enabled, then we can get only
243	 * 4-byte alignment on 32-bit kernels
244	 */
245	a = (unsigned long)kmalloc(sizeof(struct irt_entry) * num_entries + 8, GFP_KERNEL);
246	a = (a + 7UL) & ~7UL;
247	return (struct irt_entry *)a;
248}
249
250/**
251 * iosapic_load_irt - Fill in the interrupt routing table
252 * @cell_num: The cell number of the CPU we're currently executing on
253 * @irt: The address to place the new IRT at
254 * @return The number of entries found
255 *
256 * The "Get PCI INT Routing Table Size" option returns the number of
257 * entries in the PCI interrupt routing table for the cell specified
258 * in the cell_number argument.  The cell number must be for a cell
259 * within the caller's protection domain.
260 *
261 * The "Get PCI INT Routing Table" option returns, for the cell
262 * specified in the cell_number argument, the PCI interrupt routing
263 * table in the caller allocated memory pointed to by mem_addr.
264 * We assume the IRT only contains entries for I/O SAPIC and
265 * calculate the size based on the size of I/O sapic entries.
266 *
267 * The PCI interrupt routing table entry format is derived from the
268 * IA64 SAL Specification 2.4.   The PCI interrupt routing table defines
269 * the routing of PCI interrupt signals between the PCI device output
270 * "pins" and the IO SAPICs' input "lines" (including core I/O PCI
271 * devices).  This table does NOT include information for devices/slots
272 * behind PCI to PCI bridges. See PCI to PCI Bridge Architecture Spec.
273 * for the architected method of routing of IRQ's behind PPB's.
274 */
275
276
277static int __init
278iosapic_load_irt(unsigned long cell_num, struct irt_entry **irt)
279{
280	long status;              /* PDC return value status */
281	struct irt_entry *table;  /* start of interrupt routing tbl */
282	unsigned long num_entries = 0UL;
283
284	BUG_ON(!irt);
285
286	if (is_pdc_pat()) {
287		/* Use pat pdc routine to get interrupt routing table size */
288		DBG("calling get_irt_size (cell %ld)\n", cell_num);
289		status = pdc_pat_get_irt_size(&num_entries, cell_num);
290		DBG("get_irt_size: %ld\n", status);
291
292		BUG_ON(status != PDC_OK);
293		BUG_ON(num_entries == 0);
294
295		/*
296		** allocate memory for interrupt routing table
297		** This interface isn't really right. We are assuming
298		** the contents of the table are exclusively
299		** for I/O sapic devices.
300		*/
301		table = iosapic_alloc_irt(num_entries);
302		if (table == NULL) {
303			printk(KERN_WARNING MODULE_NAME ": read_irt : can "
304					"not alloc mem for IRT\n");
305			return 0;
306		}
307
308		/* get PCI INT routing table */
309		status = pdc_pat_get_irt(table, cell_num);
310		DBG("pdc_pat_get_irt: %ld\n", status);
311		WARN_ON(status != PDC_OK);
312	} else {
313		/*
314		** C3000/J5000 (and similar) platforms with Sprockets PDC
315		** will return exactly one IRT for all iosapics.
316		** So if we have one, don't need to get it again.
317		*/
318		if (irt_cell)
319			return 0;
320
321		/* Should be using the Elroy's HPA, but it's ignored anyway */
322		status = pdc_pci_irt_size(&num_entries, 0);
323		DBG("pdc_pci_irt_size: %ld\n", status);
324
325		if (status != PDC_OK) {
326			/* Not a "legacy" system with I/O SAPIC either */
327			return 0;
328		}
329
330		BUG_ON(num_entries == 0);
331
332		table = iosapic_alloc_irt(num_entries);
333		if (!table) {
334			printk(KERN_WARNING MODULE_NAME ": read_irt : can "
335					"not alloc mem for IRT\n");
336			return 0;
337		}
338
339		/* HPA ignored by this call too. */
340		status = pdc_pci_irt(num_entries, 0, table);
341		BUG_ON(status != PDC_OK);
342	}
343
344	/* return interrupt table address */
345	*irt = table;
346
347#ifdef DEBUG_IOSAPIC_IRT
348{
349	struct irt_entry *p = table;
350	int i;
351
352	printk(MODULE_NAME " Interrupt Routing Table (cell %ld)\n", cell_num);
353	printk(MODULE_NAME " start = 0x%p num_entries %ld entry_size %d\n",
354		table,
355		num_entries,
356		(int) sizeof(struct irt_entry));
357
358	for (i = 0 ; i < num_entries ; i++, p++) {
359		printk(MODULE_NAME " %02x %02x %02x %02x %02x %02x %02x %02x %08x%08x\n",
360		p->entry_type, p->entry_length, p->interrupt_type,
361		p->polarity_trigger, p->src_bus_irq_devno, p->src_bus_id,
362		p->src_seg_id, p->dest_iosapic_intin,
363		((u32 *) p)[2],
364		((u32 *) p)[3]
365		);
366	}
367}
368#endif /* DEBUG_IOSAPIC_IRT */
369
370	return num_entries;
371}
372
373
374
375void __init iosapic_init(void)
376{
377	unsigned long cell = 0;
378
379	DBG("iosapic_init()\n");
380
381#ifdef __LP64__
382	if (is_pdc_pat()) {
383		int status;
384		struct pdc_pat_cell_num cell_info;
385
386		status = pdc_pat_cell_get_number(&cell_info);
387		if (status == PDC_OK) {
388			cell = cell_info.cell_num;
389		}
390	}
391#endif
392
393	/* get interrupt routing table for this cell */
394	irt_num_entry = iosapic_load_irt(cell, &irt_cell);
395	if (irt_num_entry == 0)
396		irt_cell = NULL;	/* old PDC w/o iosapic */
397}
398
399
400/*
401** Return the IRT entry in case we need to look something else up.
402*/
403static struct irt_entry *
404irt_find_irqline(struct iosapic_info *isi, u8 slot, u8 intr_pin)
405{
406	struct irt_entry *i = irt_cell;
407	int cnt;	/* track how many entries we've looked at */
408	u8 irq_devno = (slot << IRT_DEV_SHIFT) | (intr_pin-1);
409
410	DBG_IRT("irt_find_irqline() SLOT %d pin %d\n", slot, intr_pin);
411
412	for (cnt=0; cnt < irt_num_entry; cnt++, i++) {
413
414		/*
415		** Validate: entry_type, entry_length, interrupt_type
416		**
417		** Difference between validate vs compare is the former
418		** should print debug info and is not expected to "fail"
419		** on current platforms.
420		*/
421		if (i->entry_type != IRT_IOSAPIC_TYPE) {
422			DBG_IRT(KERN_WARNING MODULE_NAME ":find_irqline(0x%p): skipping entry %d type %d\n", i, cnt, i->entry_type);
423			continue;
424		}
425
426		if (i->entry_length != IRT_IOSAPIC_LENGTH) {
427			DBG_IRT(KERN_WARNING MODULE_NAME ":find_irqline(0x%p): skipping entry %d  length %d\n", i, cnt, i->entry_length);
428			continue;
429		}
430
431		if (i->interrupt_type != IRT_VECTORED_INTR) {
432			DBG_IRT(KERN_WARNING MODULE_NAME ":find_irqline(0x%p): skipping entry  %d interrupt_type %d\n", i, cnt, i->interrupt_type);
433			continue;
434		}
435
436		if (!COMPARE_IRTE_ADDR(i, isi->isi_hpa))
437			continue;
438
439		if ((i->src_bus_irq_devno & IRT_IRQ_DEVNO_MASK) != irq_devno)
440			continue;
441
442		/*
443		** Ignore: src_bus_id and rc_seg_id correlate with
444		**         iosapic_info->isi_hpa on HP platforms.
445		**         If needed, pass in "PFA" (aka config space addr)
446		**         instead of slot.
447		*/
448
449		/* Found it! */
450		return i;
451	}
452
453	printk(KERN_WARNING MODULE_NAME ": 0x%lx : no IRT entry for slot %d, pin %d\n",
454			isi->isi_hpa, slot, intr_pin);
455	return NULL;
456}
457
458
459/*
460** xlate_pin() supports the skewing of IRQ lines done by subsidiary bridges.
461** Legacy PDC already does this translation for us and stores it in INTR_LINE.
462**
463** PAT PDC needs to basically do what legacy PDC does:
464** o read PIN
465** o adjust PIN in case device is "behind" a PPB
466**     (eg 4-port 100BT and SCSI/LAN "Combo Card")
467** o convert slot/pin to I/O SAPIC input line.
468**
469** HP platforms only support:
470** o one level of skewing for any number of PPBs
471** o only support PCI-PCI Bridges.
472*/
473static struct irt_entry *
474iosapic_xlate_pin(struct iosapic_info *isi, struct pci_dev *pcidev)
475{
476	u8 intr_pin, intr_slot;
477
478	pci_read_config_byte(pcidev, PCI_INTERRUPT_PIN, &intr_pin);
479
480	DBG_IRT("iosapic_xlate_pin(%s) SLOT %d pin %d\n",
481		pcidev->slot_name, PCI_SLOT(pcidev->devfn), intr_pin);
482
483	if (intr_pin == 0) {
484		/* The device does NOT support/use IRQ lines.  */
485		return NULL;
486	}
487
488	/* Check if pcidev behind a PPB */
489	if (pcidev->bus->parent) {
490		/* Convert pcidev INTR_PIN into something we
491		** can lookup in the IRT.
492		*/
493#ifdef PCI_BRIDGE_FUNCS
494		/*
495		** Proposal #1:
496		**
497		** call implementation specific translation function
498		** This is architecturally "cleaner". HP-UX doesn't
499		** support other secondary bus types (eg. E/ISA) directly.
500		** May be needed for other processor (eg IA64) architectures
501		** or by some ambitous soul who wants to watch TV.
502		*/
503		if (pci_bridge_funcs->xlate_intr_line) {
504			intr_pin = pci_bridge_funcs->xlate_intr_line(pcidev);
505		}
506#else	/* PCI_BRIDGE_FUNCS */
507		struct pci_bus *p = pcidev->bus;
508		/*
509		** Proposal #2:
510		** The "pin" is skewed ((pin + dev - 1) % 4).
511		**
512		** This isn't very clean since I/O SAPIC must assume:
513		**   - all platforms only have PCI busses.
514		**   - only PCI-PCI bridge (eg not PCI-EISA, PCI-PCMCIA)
515		**   - IRQ routing is only skewed once regardless of
516		**     the number of PPB's between iosapic and device.
517		**     (Bit3 expansion chassis follows this rule)
518		**
519		** Advantage is it's really easy to implement.
520		*/
521		intr_pin = pci_swizzle_interrupt_pin(pcidev, intr_pin);
522#endif /* PCI_BRIDGE_FUNCS */
523
524		/*
525		 * Locate the host slot of the PPB.
526		 */
527		while (p->parent->parent)
528			p = p->parent;
529
530		intr_slot = PCI_SLOT(p->self->devfn);
531	} else {
532		intr_slot = PCI_SLOT(pcidev->devfn);
533	}
534	DBG_IRT("iosapic_xlate_pin:  bus %d slot %d pin %d\n",
535			pcidev->bus->busn_res.start, intr_slot, intr_pin);
536
537	return irt_find_irqline(isi, intr_slot, intr_pin);
538}
539
540static void iosapic_rd_irt_entry(struct vector_info *vi , u32 *dp0, u32 *dp1)
541{
542	struct iosapic_info *isp = vi->iosapic;
543	u8 idx = vi->irqline;
544
545	*dp0 = iosapic_read(isp->addr, IOSAPIC_IRDT_ENTRY(idx));
546	*dp1 = iosapic_read(isp->addr, IOSAPIC_IRDT_ENTRY_HI(idx));
547}
548
549
550static void iosapic_wr_irt_entry(struct vector_info *vi, u32 dp0, u32 dp1)
551{
552	struct iosapic_info *isp = vi->iosapic;
553
554	DBG_IRT("iosapic_wr_irt_entry(): irq %d hpa %lx 0x%x 0x%x\n",
555		vi->irqline, isp->isi_hpa, dp0, dp1);
556
557	iosapic_write(isp->addr, IOSAPIC_IRDT_ENTRY(vi->irqline), dp0);
558
559	/* Read the window register to flush the writes down to HW  */
560	dp0 = readl(isp->addr+IOSAPIC_REG_WINDOW);
561
562	iosapic_write(isp->addr, IOSAPIC_IRDT_ENTRY_HI(vi->irqline), dp1);
563
564	/* Read the window register to flush the writes down to HW  */
565	dp1 = readl(isp->addr+IOSAPIC_REG_WINDOW);
566}
567
568/*
569** set_irt prepares the data (dp0, dp1) according to the vector_info
570** and target cpu (id_eid).  dp0/dp1 are then used to program I/O SAPIC
571** IRdT for the given "vector" (aka IRQ line).
572*/
573static void
574iosapic_set_irt_data( struct vector_info *vi, u32 *dp0, u32 *dp1)
575{
576	u32 mode = 0;
577	struct irt_entry *p = vi->irte;
578
579	if ((p->polarity_trigger & IRT_PO_MASK) == IRT_ACTIVE_LO)
580		mode |= IOSAPIC_IRDT_PO_LOW;
581
582	if (((p->polarity_trigger >> IRT_EL_SHIFT) & IRT_EL_MASK) == IRT_LEVEL_TRIG)
583		mode |= IOSAPIC_IRDT_LEVEL_TRIG;
584
585	/*
586	** IA64 REVISIT
587	** PA doesn't support EXTINT or LPRIO bits.
588	*/
589
590	*dp0 = mode | (u32) vi->txn_data;
591
592	/*
593	** Extracting id_eid isn't a real clean way of getting it.
594	** But the encoding is the same for both PA and IA64 platforms.
595	*/
596	if (is_pdc_pat()) {
597		/*
598		** PAT PDC just hands it to us "right".
599		** txn_addr comes from cpu_data[x].txn_addr.
600		*/
601		*dp1 = (u32) (vi->txn_addr);
602	} else {
603		/*
604		** eg if base_addr == 0xfffa0000),
605		**    we want to get 0xa0ff0000.
606		**
607		** eid	0x0ff00000 -> 0x00ff0000
608		** id	0x000ff000 -> 0xff000000
609		*/
610		*dp1 = (((u32)vi->txn_addr & 0x0ff00000) >> 4) |
611			(((u32)vi->txn_addr & 0x000ff000) << 12);
612	}
613	DBG_IRT("iosapic_set_irt_data(): 0x%x 0x%x\n", *dp0, *dp1);
614}
615
616
617static void iosapic_mask_irq(struct irq_data *d)
618{
619	unsigned long flags;
620	struct vector_info *vi = irq_data_get_irq_chip_data(d);
621	u32 d0, d1;
622
623	spin_lock_irqsave(&iosapic_lock, flags);
624	iosapic_rd_irt_entry(vi, &d0, &d1);
625	d0 |= IOSAPIC_IRDT_ENABLE;
626	iosapic_wr_irt_entry(vi, d0, d1);
627	spin_unlock_irqrestore(&iosapic_lock, flags);
628}
629
630static void iosapic_unmask_irq(struct irq_data *d)
631{
632	struct vector_info *vi = irq_data_get_irq_chip_data(d);
633	u32 d0, d1;
634
635	/* data is initialized by fixup_irq */
636	WARN_ON(vi->txn_irq  == 0);
637
638	iosapic_set_irt_data(vi, &d0, &d1);
639	iosapic_wr_irt_entry(vi, d0, d1);
640
641#ifdef DEBUG_IOSAPIC_IRT
642{
643	u32 *t = (u32 *) ((ulong) vi->eoi_addr & ~0xffUL);
644	printk("iosapic_enable_irq(): regs %p", vi->eoi_addr);
645	for ( ; t < vi->eoi_addr; t++)
646		printk(" %x", readl(t));
647	printk("\n");
648}
649
650printk("iosapic_enable_irq(): sel ");
651{
652	struct iosapic_info *isp = vi->iosapic;
653
654	for (d0=0x10; d0<0x1e; d0++) {
655		d1 = iosapic_read(isp->addr, d0);
656		printk(" %x", d1);
657	}
658}
659printk("\n");
660#endif
661
662	/*
663	 * Issuing I/O SAPIC an EOI causes an interrupt IFF IRQ line is
664	 * asserted.  IRQ generally should not be asserted when a driver
665	 * enables their IRQ. It can lead to "interesting" race conditions
666	 * in the driver initialization sequence.
667	 */
668	DBG(KERN_DEBUG "enable_irq(%d): eoi(%p, 0x%x)\n", d->irq,
669			vi->eoi_addr, vi->eoi_data);
670	iosapic_eoi(vi->eoi_addr, vi->eoi_data);
671}
672
673static void iosapic_eoi_irq(struct irq_data *d)
674{
675	struct vector_info *vi = irq_data_get_irq_chip_data(d);
676
677	iosapic_eoi(vi->eoi_addr, vi->eoi_data);
678	cpu_eoi_irq(d);
679}
680
681#ifdef CONFIG_SMP
682static int iosapic_set_affinity_irq(struct irq_data *d,
683				    const struct cpumask *dest, bool force)
684{
685	struct vector_info *vi = irq_data_get_irq_chip_data(d);
686	u32 d0, d1, dummy_d0;
687	unsigned long flags;
688	int dest_cpu;
689
690	dest_cpu = cpu_check_affinity(d, dest);
691	if (dest_cpu < 0)
692		return -1;
693
694	cpumask_copy(d->affinity, cpumask_of(dest_cpu));
695	vi->txn_addr = txn_affinity_addr(d->irq, dest_cpu);
696
697	spin_lock_irqsave(&iosapic_lock, flags);
698	/* d1 contains the destination CPU, so only want to set that
699	 * entry */
700	iosapic_rd_irt_entry(vi, &d0, &d1);
701	iosapic_set_irt_data(vi, &dummy_d0, &d1);
702	iosapic_wr_irt_entry(vi, d0, d1);
703	spin_unlock_irqrestore(&iosapic_lock, flags);
704
705	return 0;
706}
707#endif
708
709static struct irq_chip iosapic_interrupt_type = {
710	.name		=	"IO-SAPIC-level",
711	.irq_unmask	=	iosapic_unmask_irq,
712	.irq_mask	=	iosapic_mask_irq,
713	.irq_ack	=	cpu_ack_irq,
714	.irq_eoi	=	iosapic_eoi_irq,
715#ifdef CONFIG_SMP
716	.irq_set_affinity =	iosapic_set_affinity_irq,
717#endif
718};
719
720int iosapic_fixup_irq(void *isi_obj, struct pci_dev *pcidev)
721{
722	struct iosapic_info *isi = isi_obj;
723	struct irt_entry *irte = NULL;  /* only used if PAT PDC */
724	struct vector_info *vi;
725	int isi_line;	/* line used by device */
726
727	if (!isi) {
728		printk(KERN_WARNING MODULE_NAME ": hpa not registered for %s\n",
729			pci_name(pcidev));
730		return -1;
731	}
732
733#ifdef CONFIG_SUPERIO
734	/*
735	 * HACK ALERT! (non-compliant PCI device support)
736	 *
737	 * All SuckyIO interrupts are routed through the PIC's on function 1.
738	 * But SuckyIO OHCI USB controller gets an IRT entry anyway because
739	 * it advertises INT D for INT_PIN.  Use that IRT entry to get the
740	 * SuckyIO interrupt routing for PICs on function 1 (*BLEECCHH*).
741	 */
742	if (is_superio_device(pcidev)) {
743		/* We must call superio_fixup_irq() to register the pdev */
744		pcidev->irq = superio_fixup_irq(pcidev);
745
746		/* Don't return if need to program the IOSAPIC's IRT... */
747		if (PCI_FUNC(pcidev->devfn) != SUPERIO_USB_FN)
748			return pcidev->irq;
749	}
750#endif /* CONFIG_SUPERIO */
751
752	/* lookup IRT entry for isi/slot/pin set */
753	irte = iosapic_xlate_pin(isi, pcidev);
754	if (!irte) {
755		printk("iosapic: no IRTE for %s (IRQ not connected?)\n",
756				pci_name(pcidev));
757		return -1;
758	}
759	DBG_IRT("iosapic_fixup_irq(): irte %p %x %x %x %x %x %x %x %x\n",
760		irte,
761		irte->entry_type,
762		irte->entry_length,
763		irte->polarity_trigger,
764		irte->src_bus_irq_devno,
765		irte->src_bus_id,
766		irte->src_seg_id,
767		irte->dest_iosapic_intin,
768		(u32) irte->dest_iosapic_addr);
769	isi_line = irte->dest_iosapic_intin;
770
771	/* get vector info for this input line */
772	vi = isi->isi_vector + isi_line;
773	DBG_IRT("iosapic_fixup_irq:  line %d vi 0x%p\n", isi_line, vi);
774
775	/* If this IRQ line has already been setup, skip it */
776	if (vi->irte)
777		goto out;
778
779	vi->irte = irte;
780
781	/*
782	 * Allocate processor IRQ
783	 *
784	 * XXX/FIXME The txn_alloc_irq() code and related code should be
785	 * moved to enable_irq(). That way we only allocate processor IRQ
786	 * bits for devices that actually have drivers claiming them.
787	 * Right now we assign an IRQ to every PCI device present,
788	 * regardless of whether it's used or not.
789	 */
790	vi->txn_irq = txn_alloc_irq(8);
791
792	if (vi->txn_irq < 0)
793		panic("I/O sapic: couldn't get TXN IRQ\n");
794
795	/* enable_irq() will use txn_* to program IRdT */
796	vi->txn_addr = txn_alloc_addr(vi->txn_irq);
797	vi->txn_data = txn_alloc_data(vi->txn_irq);
798
799	vi->eoi_addr = isi->addr + IOSAPIC_REG_EOI;
800	vi->eoi_data = cpu_to_le32(vi->txn_data);
801
802	cpu_claim_irq(vi->txn_irq, &iosapic_interrupt_type, vi);
803
804 out:
805	pcidev->irq = vi->txn_irq;
806
807	DBG_IRT("iosapic_fixup_irq() %d:%d %x %x line %d irq %d\n",
808		PCI_SLOT(pcidev->devfn), PCI_FUNC(pcidev->devfn),
809		pcidev->vendor, pcidev->device, isi_line, pcidev->irq);
810
811	return pcidev->irq;
812}
813
814static struct iosapic_info *iosapic_list;
815
816#ifdef CONFIG_64BIT
817int iosapic_serial_irq(struct parisc_device *dev)
818{
819	struct iosapic_info *isi;
820	struct irt_entry *irte;
821	struct vector_info *vi;
822	int cnt;
823	int intin;
824
825	intin = (dev->mod_info >> 24) & 15;
826
827	/* lookup IRT entry for isi/slot/pin set */
828	for (cnt = 0; cnt < irt_num_entry; cnt++) {
829		irte = &irt_cell[cnt];
830		if (COMPARE_IRTE_ADDR(irte, dev->mod0) &&
831		    irte->dest_iosapic_intin == intin)
832			break;
833	}
834	if (cnt >= irt_num_entry)
835		return 0; /* no irq found, force polling */
836
837	DBG_IRT("iosapic_serial_irq(): irte %p %x %x %x %x %x %x %x %x\n",
838		irte,
839		irte->entry_type,
840		irte->entry_length,
841		irte->polarity_trigger,
842		irte->src_bus_irq_devno,
843		irte->src_bus_id,
844		irte->src_seg_id,
845		irte->dest_iosapic_intin,
846		(u32) irte->dest_iosapic_addr);
847
848	/* search for iosapic */
849	for (isi = iosapic_list; isi; isi = isi->isi_next)
850		if (isi->isi_hpa == dev->mod0)
851			break;
852	if (!isi)
853		return 0; /* no iosapic found, force polling */
854
855	/* get vector info for this input line */
856	vi = isi->isi_vector + intin;
857	DBG_IRT("iosapic_serial_irq:  line %d vi 0x%p\n", iosapic_intin, vi);
858
859	/* If this IRQ line has already been setup, skip it */
860	if (vi->irte)
861		goto out;
862
863	vi->irte = irte;
864
865	/*
866	 * Allocate processor IRQ
867	 *
868	 * XXX/FIXME The txn_alloc_irq() code and related code should be
869	 * moved to enable_irq(). That way we only allocate processor IRQ
870	 * bits for devices that actually have drivers claiming them.
871	 * Right now we assign an IRQ to every PCI device present,
872	 * regardless of whether it's used or not.
873	 */
874	vi->txn_irq = txn_alloc_irq(8);
875
876	if (vi->txn_irq < 0)
877		panic("I/O sapic: couldn't get TXN IRQ\n");
878
879	/* enable_irq() will use txn_* to program IRdT */
880	vi->txn_addr = txn_alloc_addr(vi->txn_irq);
881	vi->txn_data = txn_alloc_data(vi->txn_irq);
882
883	vi->eoi_addr = isi->addr + IOSAPIC_REG_EOI;
884	vi->eoi_data = cpu_to_le32(vi->txn_data);
885
886	cpu_claim_irq(vi->txn_irq, &iosapic_interrupt_type, vi);
887
888 out:
889
890	return vi->txn_irq;
891}
892#endif
893
894
895/*
896** squirrel away the I/O Sapic Version
897*/
898static unsigned int
899iosapic_rd_version(struct iosapic_info *isi)
900{
901	return iosapic_read(isi->addr, IOSAPIC_REG_VERSION);
902}
903
904
905/*
906** iosapic_register() is called by "drivers" with an integrated I/O SAPIC.
907** Caller must be certain they have an I/O SAPIC and know its MMIO address.
908**
909**	o allocate iosapic_info and add it to the list
910**	o read iosapic version and squirrel that away
911**	o read size of IRdT.
912**	o allocate and initialize isi_vector[]
913**	o allocate irq region
914*/
915void *iosapic_register(unsigned long hpa)
916{
917	struct iosapic_info *isi = NULL;
918	struct irt_entry *irte = irt_cell;
919	struct vector_info *vip;
920	int cnt;	/* track how many entries we've looked at */
921
922	/*
923	 * Astro based platforms can only support PCI OLARD if they implement
924	 * PAT PDC.  Legacy PDC omits LBAs with no PCI devices from the IRT.
925	 * Search the IRT and ignore iosapic's which aren't in the IRT.
926	 */
927	for (cnt=0; cnt < irt_num_entry; cnt++, irte++) {
928		WARN_ON(IRT_IOSAPIC_TYPE != irte->entry_type);
929		if (COMPARE_IRTE_ADDR(irte, hpa))
930			break;
931	}
932
933	if (cnt >= irt_num_entry) {
934		DBG("iosapic_register() ignoring 0x%lx (NOT FOUND)\n", hpa);
935		return NULL;
936	}
937
938	isi = kzalloc(sizeof(struct iosapic_info), GFP_KERNEL);
939	if (!isi) {
940		BUG();
941		return NULL;
942	}
943
944	isi->addr = ioremap_nocache(hpa, 4096);
945	isi->isi_hpa = hpa;
946	isi->isi_version = iosapic_rd_version(isi);
947	isi->isi_num_vectors = IOSAPIC_IRDT_MAX_ENTRY(isi->isi_version) + 1;
948
949	vip = isi->isi_vector = kcalloc(isi->isi_num_vectors,
950					sizeof(struct vector_info), GFP_KERNEL);
951	if (vip == NULL) {
952		kfree(isi);
953		return NULL;
954	}
955
956	for (cnt=0; cnt < isi->isi_num_vectors; cnt++, vip++) {
957		vip->irqline = (unsigned char) cnt;
958		vip->iosapic = isi;
959	}
960	isi->isi_next = iosapic_list;
961	iosapic_list = isi;
962	return isi;
963}
964
965
966#ifdef DEBUG_IOSAPIC
967
968static void
969iosapic_prt_irt(void *irt, long num_entry)
970{
971	unsigned int i, *irp = (unsigned int *) irt;
972
973
974	printk(KERN_DEBUG MODULE_NAME ": Interrupt Routing Table (%lx entries)\n", num_entry);
975
976	for (i=0; i<num_entry; i++, irp += 4) {
977		printk(KERN_DEBUG "%p : %2d %.8x %.8x %.8x %.8x\n",
978					irp, i, irp[0], irp[1], irp[2], irp[3]);
979	}
980}
981
982
983static void
984iosapic_prt_vi(struct vector_info *vi)
985{
986	printk(KERN_DEBUG MODULE_NAME ": vector_info[%d] is at %p\n", vi->irqline, vi);
987	printk(KERN_DEBUG "\t\tstatus:	 %.4x\n", vi->status);
988	printk(KERN_DEBUG "\t\ttxn_irq:  %d\n",  vi->txn_irq);
989	printk(KERN_DEBUG "\t\ttxn_addr: %lx\n", vi->txn_addr);
990	printk(KERN_DEBUG "\t\ttxn_data: %lx\n", vi->txn_data);
991	printk(KERN_DEBUG "\t\teoi_addr: %p\n",  vi->eoi_addr);
992	printk(KERN_DEBUG "\t\teoi_data: %x\n",  vi->eoi_data);
993}
994
995
996static void
997iosapic_prt_isi(struct iosapic_info *isi)
998{
999	printk(KERN_DEBUG MODULE_NAME ": io_sapic_info at %p\n", isi);
1000	printk(KERN_DEBUG "\t\tisi_hpa:       %lx\n", isi->isi_hpa);
1001	printk(KERN_DEBUG "\t\tisi_status:    %x\n", isi->isi_status);
1002	printk(KERN_DEBUG "\t\tisi_version:   %x\n", isi->isi_version);
1003	printk(KERN_DEBUG "\t\tisi_vector:    %p\n", isi->isi_vector);
1004}
1005#endif /* DEBUG_IOSAPIC */
1006